1. Field of the Invention
The present invention relates to an ink cartridge, and also to an inkjet printer to which the ink cartridge is to be attached.
2. Description of the Related Art
An ink cartridge has an ink supplying portion which supplies an ink to an inkjet printer, and an atmospheric air introducing portion through which atmospheric air is introduced into the ink cartridge. In a state where the ink cartridge is attached to the inkjet printer, atmospheric air is introduced from the outside into the ink cartridge via the atmospheric air introducing portion, and, in place of the atmospheric air, the ink in the ink cartridge is supplied from the ink supplying portion to the inkjet printer. Usually, such an ink cartridge is configured so that, in a state where the ink cartridge is not attached to an inkjet printer, the ink does not leak from the ink supplying portion or the atmospheric air introducing portion.
FIG. 30 shows an example of such an ink cartridge. In the ink cartridge, plug members 103 made of synthetic rubber are attached to an ink supplying portion 101 and an atmospheric air introducing portion 102, respectively. When the ink cartridge 100 is attached to an inkjet printer, an ink supply pipe 104 and an atmospheric air introduction pipe 105 which are disposed on the inkjet printer, which are made of a metal, and which have a needle-like hollow shape, pierce through the two plug members 103, respectively. In an ink cartridge 110 shown in FIG. 31, an ink supplying portion 111 is configured in the same manner as that of the ink cartridge of FIG. 30, but an atmospheric air introducing portion 112 is configured so that an atmospheric air introducing port 115 formed in an upper end portion of the ink cartridge 110 is closed by a seal tape 116 or the like. When the ink cartridge 110 is attached to an inkjet printer, the operator peels off the seal tape 116 to expose the atmospheric air introducing port 115 to the outside. In another ink cartridge, valve mechanisms which can prevent ink leakage from occurring are disposed in an ink supplying portion and an atmospheric air introducing portion, respectively (for example, see JP-A-2001-328279 (FIG. 1)).